A variety of threaded fasteners are used to attach license plates to automobiles or trucks. The arrangement may be as simple as a nut and a bolt. Other fasteners are provided with decorative heads, for example, as shown in U.S. Pat. No. 7,713,012 issued to Coonjohn. The threaded fasteners may in some instances be provided with clip receptacles for attachment of a removable frame that assist in retaining the license plate, as shown in U.S. Pat. No. 7,877,908 issued to Collins. Still other frames are made to bolt on using the same threaded fasteners as retain the license plate, for example, as shown in U.S. Design Pat. No. D631,415 issued to Spencer et al.
It is problematic that the license plates, which are sometimes used in conjunction with these frames, may vibrate and create undesirable noise as the vehicle is being driven. This may sometimes occur even if the fastener is fully tightened, as portions of the license plate and frame distort between the fasteners to collide with adjacent structure.